Return bend



RETURN BEND Filed July 20, 1933 a @rz f ,y f ma@ www @73, g M

July 16, 1935. .L H. TAYLOR Er AL RETURN BEND Filed July 20, 1933 3 Sheets-Sheet 5 r www# J/m 3 6%@ Patented July 16, 1935 UNITED STATES PATENT OFFICE RETURN BEND James Hall Taylor, Oak Park, and Joseph Narkiewicz, Riverside, Ill., assig'nors to Taylor Forge & Pipe Works, (.iicero, lll., a corporation of Illinois Application July 20, 1933, Serial No. 681,254

1 Claim. (Cl. 285-20) '5 the character stated which is of comparatively simple construction, can be assembled and disassembled with expedition and facility, and in which the parts of the assembly may be advantageously formed of wrought metal. A further object is the provision of a return bend of great strength in which accurate alignment and fit of the parts are assured, and leaky joints and breakage are effectively guarded against. Further objects and advantages of our invention will appear from the detail description.

In the drawings:-

Figure 1 is a plan view, partly broken away, of a return bend embodying our invention;

Figure 2 is a section taken substantially on line 2-2 of Figure 1;

Figure 3 is a section taken substantially on line 3--3 of Figure 2;

Figure 4 is a plan view of the return bend with the return fitting and securing means therefor omitted for clearness of illustration;

K Figure 5 is a view similar to Figure 2 but showing a modified form of return bend embodying our invention; and

Figures 6, 7 and 8 illustrate successive steps in welding the pressure receiving bosses onto the return fitting.

The return bend of our invention comprises two cylindrical headers I, each provided, at its inner end, with a suitable recess 2 for reception of the end portion of a wrought metal still tube the end of which is expanded'or rolled into this recess in a known manner. Each header is further provided with a flared opening extendingfrom the outer end of recess 2 and providing a. tapered seat 3 for the correspondingly tapered end portion of a return fitting 4. This fitting extends through slots 5 in the headers, each of which is provided with two diametrically opposite -openings 6 of substantially rectangular shape, the outer end portion of each opening being of approximately semi-circular shape, as at 6a.

The openings 6 receive the end portions of pressure bars 1, the ends of these bars being inclined at la. The portion of bar 'I remote from the return tting is rounded at Ib and seats against the semi-circular wall 6a of opening 6 to permit of rocking movement of the bar. Bar J is provided, at its central portion, with.an elliptical enlargement or body 8 which is suitably bored and threaded for reception of a pressure screw 9.

This screwV is provided with a rounded end IIJ which lits into a corresponding recess Il in a boss I2 rigid with tting 4. The screw 9 is coaxial with recess 2 of header I so that the return fitting 4 is subjected to pressure axially of the tubes, by the screws 9, and the ends of this tting are held securely seated in the headers so as to eiect fluid tight closures therewith. The ability of the pressure bars to rock slightly, in conjunction with the rounded ends of the screws and the corresponding recesses in the bosses I2, contributes to accurate alignment of the parts in securing the return fitting in the headers.

Each of the headers I is provided, adjacent the inner `end thereof, with two circumferential grooves I3 and I4 which dene a shoulder I5. 'Ihe opposite faces I6 of this shoulder are inclined and converge inward of the header so as to provide, in eifect, clamping ribs I 'I of approximately V-shape in cross-section, these ribs projecting Vtoward the opposite ends of the header.

Clamping blocksv I8 are disposed between the headers and serve as spacing members to hold the headers in spaced relation and out of contact with each other. Each of these blocks is provided with two lateral clamping elements in the form of ribs I9 which conform in cross-section to the grooves I3 and I4 and have inclined faces disposed to contact the inclined faces I6 of shoulder I5. The elements I9 are of arcuate shape, preferably being concentric with the respective headers and extending an appreciable distance circumferentially about the latter, as shown more clearly in Figure 4.

'I'he'blocks I8 are forced toward each other by means of nuts 20 screwing upon the ends of a bolt 2| which passes through the clamping blocks centrally thereof. After the return bend has been assembled, and before the pressure screws 9 and the nuts 20 have been turned up tight, either of the headers I may be turned sufficiently to -correct any slight inaccuracies in alignment, independently of the other header, which facilitates accuracy in assembly. After the parts have been accurately aligned, the pressure screws 9 and the nuts 20 may be turned tightly into position. The clamping blocks I8 secure the headers tightly together so as to prevent effectively relative movement thereof, and also serve to hold them out of contact with each other. This is advantageous in that, if the headers were in contacting relation relative movement therebetween, due to expansion and contraction or other causes, would exert a powerful leverage effect which might well result in breakage of parts of the assembly or opening of the joints thereof. The headers are formed of Lwrought metal, preferably alloy steel of suitable hardness for the purposes intended, and are of cylindrical shape and uniform diameter. This assures that the inner ends of the headers, in which the wrought metal tubes and the ends of the iitting seat, are of uniform cross-section and have uniform expansion and contraction, which contributes to maintaining the joints tight and to long life of the assembly. The tting 4 is also formed of wrought alloy steel, or other suitable wrought metal, and the bosses I2 may be formed integrally with this fitting, as in Figure 2, or welded thereto as will be hereinafter described.

Having Athe header structure and the return fitting of wrought metal, as well as the still tubes, has the advantage that more nearly equal expansion and contraction of the parts of the assembly is assured, than is possible when the header structure is of other than wrought metal. This eliminates the danger of leaky joints or breakage due to unequal expansion and contraction of parts of the assembly.

In the modified form illustrated in Figure 5, each of the headers, IIl is provided with an annular shoulder 22 dening an opening 23 aligned with the-outer end of a wrought steel still tube 24 the end of which is secured in recess 2B.. The outer face of 1 shoulder 22 is rounded at 25 to provide a. seat for the end of a wrought; metal return fitting 26, the ends of which are ground out at 28'L to seat accurately upon the shoulders 22 and form iluid tight and pressure resistant closures therewith.

Since thev iltting 26 is ot wrought metal, we preier to form this fitting first and then unite the pressure receiving bosses therewith by welding. The method of applying these bosses is illustrated in Figures 6, 'I and 8. A steel block 21, of approximately crescent shape in plan, is properly positioned at the upper -end portion of iitting 26. This block is then welded to the fitting at 28, the block serving as a dam and restraining iiow of the welding metal downward along the fitting. 'I'he welding is continued until the space between the block and the tting is completely filled in, with the surface of the welded in metal ilush with the upper or outer surfaceof the block. This is shown in Figure 8, Iin which the tting has been turned through approximately ninety degrees so as to render readily accessible the space between the tting and the lower or inner face of the block. Metal is then welded into the space between the inner face of the block and the tting, as at 29 in Figure 8, and this space is completely filled with welded in metal. This is clearly illustrated in Figure 5. The block 2l and the two bodies 28 and 29 of welded in metal are integrally united and form a boss 30 which forms an integral part of the iltting 26. This boss is provided with a rounded depression I Il which receives the rounded inner end vof the pressure screw 9, as above described.

The rounded outer surfaces 25 of the shoulders 22 and the complementary surfaces 26* of the tting 26 provide ball and socket joints between the shoulders and the ends of the fitting. This is advantageous in that it permits compensation for any Aslight inaccuracies in alignment of parts of the assembly. The use of wrought metal headers and a wrought metal return iitting possesses the advantage that the metal of these parts is compacted and non-porous, which renders psible an accurate fit and assures tight closures at all times between the elements of the ball joints, as well as long life of the parts. Likewise, the use of wrought metal parts in the form of our invention illustrated in Figures 1 to 4, inclusive, assures more accurate t and tighter closures at the joints than would be possible if parts of cast metal or other relatively porous material were employed.

'What we claim is:-

' In a return bend, a pair of headers each adapted at one end for reception of a still tube, the respective headers at said end thereof being cylindrical and each provided with an upwardly proj ecting concentric rib and a downwardly projecting concentric rib, upper and lower clamping blocks disposed between said ends of the headers, each block having clamping ribs interengaging the ribs of the headers, the ribs of said blocks being concentric with said ends of the headers and accommodating relative turning movement of the latter on their respective axes in the assembling and adjustment of the return bend, and means for" forcing the clamping blocks one toward the other.

' JAMES HALL TAYLOR. JOSEPH NARKIEWICZ. 

